The Studies of Comparative Treatments for REtinal Vein Occlusion 2 (SCORE2) is a phase III trial to study patients with central retinal vein occlusion. This comparative effectiveness research proposal aims to support a multicenter, prospective, randomized, phase III clinical trial to compare treatment protocols for decreased vision due to macular edema secondary to central retinal vein occlusion (CRVO). Currently, two anti-vascular endothelial grown factor (VEGF) compounds, bevacizumab and ranibizumab, have become first-line therapy in CRVO eyes that have vision loss due to macular edema. The newest anti-VEGF molecule, aflibercept, was recently shown to be effective in patients with macular edema due to CRVO in the COPERNICUS Study sponsored by Regeneron Pharmaceuticals Inc (Tarrytown, NY). The SCORE2 trial is a noninferiority trial between a first generation anti-VEGF treatment, bevacizumab, and a second generation anti-VEGF treatment, aflibercept. The noninferiority margin will be set at an Early Treatment Diabetic Retinopathy Study visual acuity letter score of 5. In SCORE2, patients will be assigned randomly to 1) intravitreal aflibercept every 4 weeks or 2) intravitreal bevacizumab every 4 weeks. The primary noninferiority comparison between the 2 groups will be performed at 6 months. At 6 months, participants assigned to aflibercept injection at baseline that meet the criteria for a good response will be randomized to either continuing aflibercept every 4 weeks vs. changing to a fixed regimen of every 8 weeks. This will allow for an assessment of whether a fixed regimen of every 8 week injections can produce visual results similar to continued treatment Q4 weeks. At 6 months, participants assigned to bevacizumab at baseline that meet the criteria for a good response will be randomized to either continuing bevacizumab injection every 4 weeks vs. changing to a pro re nata (PRN) regimen with monthly assessement. This will allow for an assessment of whether a PRN regimen can produce visual results similar to continued treatment every 4 weeks. All participants will be followed for 13 months.